evaluation of hospital inpatient complications

7/23/2019 Evaluation of Hospital Inpatient Complications

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RESEARCH ARTIC LE Open Access

Evaluation of hospital inpatient complications:a planning approachRonald J Lagoe1 , Gert P Westert2*

Abstract

Background: Hospital inpatient complications are one of a number of adverse health care outcomes. Reducingcomplications has been identified as an approach to improving care and saving resources as part of the healthcare reform efforts in the United States.An objective of this study was to describe the Potentially Preventable Complications software developed as a toolfor evaluating hospital inpatient outcomes. Additional objectives included demonstration of the use of this soft-ware to evaluate the connection between health care outcomes and expenses in United States administrative dataat the state and local levels and the use of the software to plan and implement interventions to reduce hospitalcomplications in one U.S. metropolitan area.Methods: The study described the Potentially Preventable Complications software as a tool for evaluating theseinpatient hospital outcomes. Through administrative hospital charge data from California and Maryland andthrough cost data from three hospitals in Syracuse, New York, expenses for patients with and withoutcomplications were compared. These comparisons were based on patients in the same All Patients RefinedDiagnosis Related Groups and severity of illness categories. This analysis included tests of statistical significance.In addition, the study included a planning process for use of the Potentially Preventable Complications software inthree Syracuse hospitals to plan and implement reductions in hospital inpatient complications. The use of the PPCsoftware in cost comparisons and reduction of complications included tests of statistical significance.

Results: The study demonstrated that Potentially Preventable Complications were associated with significantlyincreased cost in administrative data from the United States in California and Maryland and in actual cost datafrom the hospitals of Syracuse, New York. The implementation of interventions in the Syracuse hospitals wasassociated with the reduction of complications for urinary tract infection, decubitus ulcer, and pulmonaryembolism.Conclusions: The study demonstrated that the Potentially Preventable Complications software could be used toevaluate hospital outcomes and related costs at the aggregate and diagnosis specific levels. It also indicated thatthe system could be used to plan and implement interventions to improve outcomes on an individual ormultihospital basis.

BackgroundInterest in the improvement of quality and outcomes inhealth care is increasing in both Europe and the UnitedStates. Initially, this development was driven mainly by attention to improving care at the patient level [ 1].More recently, however, a linkage between improvingoutcomes and saving health care costs has developed.

An important study evaluated the direct medical costsof a wide range of adverse events in hospitals in theNetherlands. This study included unplanned admissions;unplanned readmissions; hospital acquired complica-tions including infections, neurological complications,and other diagnoses; unexpected mortality, and otherissues. A study of a wide range of adverse medicalevents in hospitals in the Netherlands suggested that30,000 inpatient admissions included a preventableadverse event. On the basis of data collected in 2004, itestimated that the annual costs of preventable adverse

* Correspondence: [email protected] National Institute for Public Health and the Environment Bilthoven,Netherlands

Lagoe and Westert BMC Health Services Research 2010, 10 :200http://www.biomedcentral.com/1472-6963/10/200

2010 Lagoe and Westert; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the CreativeCommons Attribution License (http://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, andreproduction in any medium, provided the original work is properly cited.
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events in Dutch hospitals was 161 million euros [ 2].Other European studies have evaluated potentially pre- ventab le mortal ity in Dutch hosp ital s [ 3], hospitalacquired urinary tract infections [ 4], nosocomial pneu-monia [ 5,6], hospital acquired infections [ 7], pressureulcers [8], and adverse events in British Hospitals [ 9].The Hoonhout and Zegers studies were carried outthrough the Netherlands adverse events research andused the same databases.

Studies have also evaluated the financial impact of adverse health care outcomes and related issues in theUnited States including surgical site infections [ 10,11],urinary tract infections [ 12], clostridium difficile [13],and hospital acquired pressure ulcers [ 14]. Like theirEuropean counterparts, some of these have includedefforts to address the relationship between health careoutcomes and costs [ 15].

The context of health care reform in national politicshas become increasingly important for evaluation andimprovement of hospital outcomes. This context relates tothe process of health care reform and the development of software to define and analyze these outcomes. Despiteincreasing interest in the subject, research concerning thecosts of adverse health care outcomes and efforts toaddress them have been hampered by the lack of majorprovider incentives for quality improvement and the diffi-culties of data collection in this area. Recent developmentssuggest that situation is changing in the United States.

Evidence is growing that the health care reform move-ment in the United States that was stimulated by theObama Administration will attempt to reduce providerreimbursement for adverse clinical outcomes. A majordriver of this process has been increased public aware-ness of the high level of health care spending in theUnited States. Within the health care reform debate, theObama Administration has repeatedly emphasizedthe lack of connection between high levels of healthcare expenditures and outcomes such as life expectancy and mortality compared with other nations [ 16-18].

These issues have been complicated by the impact of the economic recession of 2008 and 2009. The need forincreased government spending by the U.S. federal gov-

ernment to stimulate economic recovery has been con-strained by the continued increase in public expendituresfor health care through the Medicare and Medicaid pro-grams [19]. In his Inaugural Address, President Obamacalled for higher quality of care at reduced costs [ 20].

In this context, it has been suggested that inpatienthospital complications generate large expenses in Eur-ope and the United States. These complications arediagnoses which developed after admission to inpatienthospital beds. These complications are defined as harm-ful events or negative outcomes occurring during inpati-ent hospitalization that result from the processes of care

and treatment rather than the natural progression of diseases [11].

Inpatient hospital complications are important becausethey can result in substantial adverse outcomes forpatients. Events such as infections and circulatory com-plications cause considerable discomfort for patients,sometimes with life threatening consequences. Theseevents disrupt the patients recovery as well as theirreturn to residential environments and employment.Because complications can extend hospital stays andconsume additional resources, they can also block accessto hospital beds for other patients.

Inpatient complications are also costly. They resultin large expenditures for additional nursing time,pharmaceuticals, and tests before discharge is possible.Although the frequency of complications is often low,the total additional expenditures can be large at the pro-

vider and system wide levels [16].Fortunately, the rising interest in improving the quality

of care as a means of reducing costs are being supportedby the availability of new resources for the collection andanalysis of health care outcomes data. These include new administrative data categories which address outcomessuch as inpatient hospital complications and computersoftware such as the Potentially Preventable Complica-tions system developed by the 3M Corporation whichwas created to analyze these indicators [ 21]. The Poten-tially Preventable Complications system was developed toevaluate inpatient hospital outcomes based on adminis-trative data. The system has been validated in preliminary studies by the New York State Department of Health andthe Massachusetts Hospital Association. The system iscurrently being evaluated in a series of demonstrationprojects in the United States.

This objective of this study was to describe the Poten-tially Preventable Complications software as a tool forevaluating hospital inpatient outcomes. The study showed the use of this software to analyze the connec-tion between health care outcomes and expenses in Uni-ted States administrative data at the state and locallevels. The study also described the use of the softwareto plan and implement interventions to reduce hospital

complications in one U.S. metropolitan area.The data used in this study are openly available.

Administrative databases include patient specific databut may, in some cases, limit the availability of uniquepatient identifiers.

MethodsPotentially Preventable ComplicationsPotentially Preventable Complications is a system forcategorizing and evaluating inpatient hospital complica-tions developed by the 3M Corporation. The followingmaterial describes the specific components of this


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system within the context of hospital outcomesimprovement.

The PPC system provides information concerning afull range of complications, as well as individual cate-gories for health care providers [ 21]. The complicationsincluded in the system were identified through a review of existing literature, the diagnosis codes used in theComplications Screening Protocol developed by Iezzoniet al, and the Patient Safety Indicators developed by theAgency for Healthcare Research and Quality [ 22,23].

The full list of PPCs includes 64 mutually exclusivecategories that were identified from ICD-9-CM proce-dure codes for secondary diagnoses. These diagnoses areidentified as clinical conditions that were not the princi-pal causes of hospital admission. The 64 categories havebeen condensed to a summary list of 35 PPCs. This pro-cess was carried out in order to support clinical man-

agement of related diagnoses in hospitals. It was basedon clinical management needs, rather than scientific evi-dence concerning these diagnoses. 3M Health Informa-tion Services is currently developing a revised PPCalgorithm based on ICD-10 codes. That process isscheduled for completion in 2011. The summary list fol-lows in Table 1.

Under the Potentially Preventable Complication sys-tem, a number of diagnoses are excluded as non preven-table. These include complications directly related tomalignant diseases, multiple trauma, organ transplants,specific burns, and HIV related disorders. Because of their unique characteristics, neonates are also excluded.A number of these diagnoses are excluded by the algo-rithm as global exclusions, whether they appear as prin-cipal or secondary diagnoses. Others are excluded only when accompanied by another specific diagnosis [ 21].

The Potentially Preventable Complications systememploys administrative hospital data. Within thesedata, the Present on Admission indicator is used toidentify diagnoses which develop after admission toacute hospitals. The Present on Admission Indicator isapplied to each secondary diagnosis of each hospitalinpatient. Each of these diagnoses are identified aspresent on admission, not present on admission, or

undetermined.Use of the Present on Admission indicator on a wide-

spread basis in the United States was made possible by National Uniform Billing Committee changes (UB 04)approved May 23, 2007. Under these changes, the stan-dard inpatient claim form was modified to allow thesubmission of a Present on Admission indicator foreach secondary diagnosis [ 24]. A number of state databases have followed Medicare by requiring hospitals touse this indicator.

The validity of the Present on Admission indicator isbased on the degree of compliance of hospital staffs

with Medicare criteria for this indicator. It was man-dated for use throughout the United States by Medicarein 2007. In New York State, this indicator has been usedsince the mid 1990s. It is assumed that the extensiveexperience of New York State and the Syracuse hospitalswith the Present on Admission indicator contributed tothe validity of related data used to define PPCs [ 25]. Atthe same time, this experience is based on unpublisheddata which has not benefited from extensive evaluation

Table 1 PPC Summary Categories01 Stroke & Intracranial Hemorrhage

02 Extreme CNS Complications

03 Acute Pulmonary Edema and Respiratory Failure with MechanicalVentilation

04 Pneumonia & Other Lung Infections

05 Aspiration Pneumonia

06 Pulmonary Embolism

07 Shock

08 Congestive Heart Failure

09 Acute Myocardial Infarct

10 Ventricular Fibrillation/Cardiac Arrest

11 Peripheral Vascular Complications Except Venous Thrombosis

12 Venous Thrombosis

13 Major Gastrointestinal Complications with Transfusion or SignificantBleeding

14 Major Liver Complications15 Clostridium Difficile Colitis

16 Urinary Tract Infection

17 Renal Failure with Dialysis

18 Post-Hemorrhage & Other Acute Anemia with Transfusion

19 Decubitus Ulcer

20 Septicemia & Severe Infections

21 Post-Op Wound Infection & Deep Wound Disruption withProcedure

22 Reopening Surgical Site

23 Post-Op Hemorrhage & Hematoma with Hem Cntrl Proc or I&DProc

24 Accidental Puncture/Laceration during Invasive Procedure25 Post-Procedure Foreign Bodies

26 Encephalopathy

27 Iatrogenic Pneumothrax

28 Mechanical Complication of Device, Implant & Graft

29 Inflammation & Other Complications of Devices, Implants or GraftsExcept Vascular Infection

30 Infections Due to Central Venous Catheters

31 Obstetrical Hemorrhage with Transfusion

32 Obstetric Laceration & Other Trauma without Instrumentation

33 Obstetric Laceration & Other Trauma with Instrumentation

34 Major Puerperal Infection and Other Major Obstetric Complications

35 Post-Op Respiratory Failure with Tracheostomy


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and scrutiny. For this reason, additional evaluation of the reliability of the Present on Admission data isnecessary.

Under the Potentially Preventable Complications sys-tem, candidate diagnoses are those that are not excludedat the global or specific levels. These diagnoses are iden-tified as not present on hospital admission. The candi-date diagnoses are evaluated with respect to risk of complications based on reasons for admission and sever-ity of illness. Evaluation of risk of complications basedon reason for admission is related to hospital servicesprovided to each patient. A major factor in this evalua-tion is the type of hospital service, whether medical orsurgical, that a patient receives. The susceptibility of complications varies widely among medical and surgicalpatients. For example, among medicine patients, aspira-tion pneumonia is more likely to develop as a complica-

tion for a patient with stroke as a principal diagnosisthan for one with urinary retention. The type of surgery is also a major influence on the likelihood of specificcomplications [ 21].

Risk of complications is also closely related to theseverity of illness of each patient. Those hospitalized withsevere secondary diagnoses or with multiple comorbid-ities have a higher risk of developing complications thanthose who do not [ 26,21]. The Potentially PreventableComplication system employs the All Patients Refinedalgorithm to determine severity of illness. This algorithmemploys degree of illness based on principal and second-ary diagnoses identified by (ICD-9-CM) medical recordcodes, patient age, and other factors [ 27].

The use of severity of illness to evaluate risk of hospi-tal complications makes it possible to compare risklevels within or between hospitals under the Potentially Preventable Complications System. Within this context,comparisons can be developed within the same hospital,for different hospitals, or between hospitals and regionalbenchmark populations. For this reason, comparisons of populations need to be stratified by Diagnosis RelatedGroup and severity of illness. This capability is limitedby the fact that secondary diagnoses and comorbiditiesthat are complications also influence severity of illness

within Diagnosis Related Groups. For example, thedevelopment of pneumonia as a post admission compli-cation could cause the severity of illness of a medical orsurgical inpatient to increase from 1 (Minor) to 2 (Mod-erate). A post admission complication for urinary tractinfection would have a similar impact. The impact of this phenomenon can be limited by the fact that inpati-ent complication rates are generally relatively low.

The Potentially Preventable Complications systemhas made it possible to evaluate the financial impactof these outcomes in acute hospitals. Because compli-cations are identified by All Patients Refined Severity of

Illness, it is possible to identify at risk populations andpopulations who experience each complication by DRGand severity. The hospital charges for these populationscan then be compared using administrative data. Thesedata are based on reported charges by hospital. Becausecharges are all inclusive, they can contain actual costs aswell as provider mark ups. In the study cited, they wereassumed to be generally representative of actual hospitalcosts. It must be emphasized, however, that the quanti-tative relationship varies by hospital because of differ-ences in cost accounting and provider mark ups [ 24].

The Potentially Preventable Complications system iscurrently being tested at a number of hospitals in theUnited States. State governments and private organiza-tions will be using the system for public and providerreporting of outcomes data.

Potentially Preventable Complications AppliedThe application of the Potentially Preventable Complica-tions system to hospital quality improvement is illu-strated by the experiences of the acute care facilities of Syracuse, New York. The metropolitan area of Syracuse,New York includes a resident population of 446,065[28] and four urban hospitals. The hospitals, which gen-erate approximately 70,000 discharges annually, havehistorically worked to improve efficiency and outcomesthrough their cooperative planning organization, theHospital Executive Council [ 29].

The Syracuse hospitals became interested in using thePotentially Preventable Complications system for differ-ent reasons. One of these was the commitment of theObama Administration to reducing health care costs by improving the quality of care. The Administration hassuggested that reduction of complications will be animportant part of its health care reform program. TheObama Administration has indicated that it will bedeveloping financial mechanisms for reducing complica-tions as part of the implementation of its health carereform program during 2011 and 2012. In New YorkState, reduction of complications through the use of PPCs has been included in the Governor s proposedbudget for 2010 - 2011.

Another major influence on the Syracuse hospitals wasthe potential for internal cost savings. Preliminary inpa-tient data developed by the Hospital Executive Counciland the Syracuse hospitals suggested that the actualcosts of treating patients with PPCs was substantially higher than the costs of treating patients with the sameAPR DRGs and severity levels without the complica-tions. The data were based on actual hospital costsrather than charges. These costs were developed usingcost accounting systems at the individual hospitals.

In this study, the Potentially Preventable Complica-tions categories were employed as a component of the


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Method. This was based on the need to test the use of these categories in addressing inpatient complications. Itwas not within the scope of this study to test or adjustthe content of the PPC categories.

The program for reduction of Potentially PreventableComplications in the Syracuse hospitals was developed jointly by hospital staff members identified by the Chief Executive Officers, the Hospital Executive Council staff,and representatives of 3M Health Information Services.It included the following components.

Data Development and DistributionEducational ProgramClinical Record ReviewsSelection of Objectives by PPC Category Identification of Drivers of ComplicationsIdentification and Implementation of Interventions

At the beginning of the project, the 3M Potentially Preventable Complications Software was still under devel-opment and could not be transferred. As a result, theinitial monitoring data were produced directly by 3M

and distributed in Syracuse through the Hospital Execu-tive Council. These data included summary tables con-taining PPC frequencies and rates per at risk dischargesfor the individual hospitals and severity adjusted bench-mark populations. These data were produced for the 35PPC summary categories. They also included patientspecific summary data for the hospital PPC and at riskpopulations. Initial data provided were for the periodsJanuary - December 2007 and January - June 2008.

The project also involved presentation of an educa-tional program to key hospital staff members. Theprogram involved teleconferences concerning the Poten-tially Preventable Complications System by senior staff of 3M Health Information Services to hospital adminis-trators, physicians, and quality assurance staff. Thesepresentations described the development and structureof the PPC algorithm, as well as its potential uses toimprove outcomes and reduce costs.

Following the educational presentations, each hospitalused the Potentially Preventable Complications informa-

tion which had been provided to conduct reviews com-paring the information produced by the software withclinical data in patient charts. At three of the hospitals,the data produced by the software was found to be con-sistent with data in the charts. At the fourth hospital, itwas determined that the existence of numerous falsepositives in the complications data would require arecoding process. This process was necessary to verify the presence of inpatient complications based on docu-mentation in the patient records.

The next phase of the process was identification of Potentially Preventable Complications categories that

were to be the objectives of the quality assuranceprocess. Within each of these categories, the hospitalsidentified drivers of the complications and developedinterventions to address the drivers. These activitieswere followed by the implementation of interventionsbetween October 2008 and March 2009.

The interventions developed in the Syracuse hospitalsfocused on urinary tract infections, pneumonia, clostri-dium difficile colitis, decubitus ulcer, pulmonary embo-lism, and post hemorrhagic and other acute anemia withtransfusion. Each hospital identified specific PPCs thatwould be the focus of its interventions. These selectionswere based on historical complication rates, hospitalresources, and quality assurance objectives. The data inTable 2 identify numbers of hospital complications andcomplication rates compared with severity adjustedbenchmarks for each PPC that was a focus on an inter-

vention by the participating hospitals.Interventions addressing urinary tract infections at

Community-General and Crouse hospitals focused ondevelopment of protocols for urine sample collectionand nursing procedures regarding catheter insertion,removal, and care. Educational programs were devel-oped to implement these procedures at the two hospi-tals. At Crouse Hospital, stickers were developed forattachment to patient charts to remind nurses of theneed for vigilance in this area. At Community-General,stamps were placed in patient charts to remind physi-cians to reorder or discontinue the catheters. At bothhospitals, interventions also included daily monitoringof patients for sites of infection and laboratory work.The Crouse and Community-General programs wereimplemented in October 2008.

For pneumonia at St. Joseph s Hospital Health Center,a large majority of the complications were produced by surgery, especially cardiac and orthopedic surgery. Itwas determined that the principal drivers of this com-plication were ventilator use and failure to implementearly ambulation of post surgery patients. In order toaddress this complication, the hospital developed interventions addressing ventilator associated pneumoniain October 2008. Additional protocols addressing

community-acquired pneumonia, which included expe-dited ambulation of patients after surgery, were alsoimplemented.

For clostridium difficile colitis (c. diff.) at Community-General Hospital, the principal driver was determined tobe environmental because this infection can remain inthe environment for long periods of time and culturedfrom almost any surface. Complications of influenzawere also a potential driver, since they disrupt normalintestinal flora, leading to an overgrowth of c diff. Inter- vent ions were identi fied for th is PPC includingimproved cleaning procedures in treatment and patient


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rooms, isolation of at risk patients, hand washing withsoap rather than sanitizers, and increased cleaningtimes. It involved cleaning procedures in treatment andpatient rooms using bleach sufficient to address theresistant nature of this organism. These procedureswere developed and implemented by the nursing andhousekeeping staffs of the hospital.

Two of the hospitals developed planning processesfocusing on decubitus ulcers as complications. The plan-ning process at both hospitals identified a number of drivers of decubitus ulcer development including thelack of skin assessments for patients at the time of admission including staging of these complications, thelack of complete care plans for ulcer assessment, theneed for reassessment of changes in the complication,and the lack of pressure sensitive mattresses on someunits.

Interventions developed to address these needsfocused on complete wound care planning includingassessment at the time of admission and reassessmentsduring the stay. At Crouse Hospital, these procedureswere to be implemented by a multidisciplinary team.Interventions also included installation of pressure sensi-tive mattresses for all medical-surgical beds. Becauseplanning activities at both Crouse Hospital and St.Joseph s Hospital Health Center were completedbetween during the third quarter of 2008, the interven-tions were implemented soon after.

At Crouse Hospital, the planning process identified thedrivers of the pulmonary embolism complication as thelack of procedures to identify patients at risk and the lackof a protocol and education plan for management of

these patients. Interventions focused on development of these procedures and updating orthopedic pathways forfractured hip, total hip replacement, and joint replace-ment to include them. The development of a protocol toaddress the range of patient diagnoses identified with aPPC of pulmonary embolism in the 3M data requiredmore time than had been anticipated. As a result, theprotocol was not finalized and implemented until the sec-ond quarter of 2009.

The planning process for post hemorrhagic and acuteanemia involved record review issues at two acute carefacilities. Crouse Hospital developed an analysis of trans-fusion cases using patient charts and determined that aminority actually addressed PPC criteria. Procedures forcoding this condition were revised to ensure that datagenerated reflected actual experience. St. Joseph s Hospi-tal Health Center identified coding issues differentiatingexpected and acute blood loss anemia. In addition, theHospital identified the lack of standards of care fortransfusions as potential drivers of this complication. Toaddress this driver, standards of care and transfusiontriggers for physicians were revised. These procedureswere implemented in the fourth quarter of 2008.

ResultsThe initial results of the study involved the developmentof financial data concerning Potentially PreventableComplications. The financial analysis included adminis-trative charge data from the states of California andMaryland analyzed by the 3M Health Information Ser- vices staff. It also included a brief, summary analysis of actual cost data from the Syracuse hospitals evaluated

Table 2 Potentially Preventable Complications Programs Implemented between October - December 2008 SyracuseHospitals January - June 2008

Discharges with Major PPCTotal Cases

Major PPC Rate/ 1,000

% Difference Significance Level

Actual Expected Actual Expected

Urinary Tract InfectionCrouse Hospital 43 55.9 5.43 7.05 -23.03Community General Hospital 46 41.3 12.65 11.34 11.49

PneumoniaSt. Joseph s Hospital Health Center 145 112.0 10.09 7.79 29.46 p < 0.05

Clostridium Difficile ColitisCommunity General Hospital 12 4.9 2.99 1.22 144.20

Dccubitus UlcerCrouse Hospital 6 7.1 0.71 0.85 -15.69St. Joseph s Hospital Health Center 31 13.0 3.41 1.43 138.47 p < 0.05

Pulmonary EmbolismCrouse Hospital 12 5.1 1.53 0.65 133.80 p < 0.05

Post-Hemorrhage & Another Acute Anemia w TransfusionSt. Joseph s Hospital Health Center 55 16.0 7.36 2.14 243.75 p < 0.05

Sources: Hospital Executive Council; 3M Health Information Systems.


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by the Hospital Executive Council. These two analyses,based on different data sets and indicators, wereintended to provide estimates concerning the impact of inpatient complications on hospital costs.

Analysis of the charge data involved editing of infor-mation submitted by hospitals. Patient data that wereincomplete, or based on a discharge status of transferredto another acute care facility or expired were excluded.It has been estimated that these data involved a maxi-mum of 6 percent of the records from each state. Theresulting information from the California Office of Sta-tewide Health Planning and Development was based onfiscal year 2008 (July 2007 - June 2008) and included235 hospitals. The resulting information from the Mary-land Health Services and Cost Review Commission wasbased on fiscal year 2008 (October 2005 - September2006) and included 43 hospitals [ 24].

The information from Maryland included uniformcategories of financial data that made it possible to esti-mate costs accurately from charge data. The Californiacharge data did not include this level of structure andwere evaluated using a charge to cost ratio of 1.264. Aregression model was applied to both data sets to esti-mate average costs per patient by Potentially PreventableComplications. Examples of incremental costs added topatient expenses for PPCs with the highest frequenciesin both states are identified in Table 3[24].

The data in Table 3 indicate that the mean incremen-tal costs per Potentially Preventable Complication weresimilar. It was notable that different data bases and needfor separate statistical methods produced estimatedincremental costs that did not vary greatly. At thepatient level, the estimated impact of these costs wassubstantial. The incremental costs of the complicationsfor these categories ranged from $4,950 to $25,401 inCalifornia and from $3,910 to $16,709 in Maryland [ 24].These data included results from the study, rather thana separate analysis.

In the development of their demonstration programconcerning Potentially Preventable Complications, theHospital Executive Council and the Syracuse hospitalsalso produced estimates of the impact of these outcomeson hospital costs. Like the evaluations involving theCalifornia and Maryland data, these comparisons werebased on inpatient populations with the same APRDRGs and severity of illness levels that experienced thePPCs and patients with the same risk characteristicswho did not experience the PPCs. The Syracuse com-parisons, however, were based on actual cost data fromthe hospitals. Through this stratification, to the extentpossible, the differences in costs identified resulted fromthe complications involved, rather than variations indiagnoses and severity of illness of the populations.

Examples of the cost analyses from three of the Syracusehospitals are summarized in Table 4. They include dis-

charges, total costs, and mean costs per discharge forselected PPCs during the period before implementation of the demonstration program. The comparisons were basedon patients with and without each PPC who were assignedto the same All Patients Refined Diagnosis Related Groupsand severity of illness levels within these APR DRGs.

The comparisons of actual costs from the Syracusehospitals, like those from California and Maryland, sug-gested the substantial impact of complications onexpenses for hospital inpatients. For patients with urin-ary tract infection, clostridium difficile colitis, and decu-bitus ulcer at Community-General Hospital, mean costsfor patients with the complication were more than dou-ble those for the same at risk populations without it.For patients with urinary tract infection at Crouse Hos-pital, pneumonia at St. Joseph s Hospital Health Center,and decubitus ulcer as a PPC at both hospitals, expenseswere several times those for at risk groups without thecomplications. A portion of this may have resulted fromsurgery patients and those with higher severity of illnessat those hospitals. These comparisons were developed

Table 3 Estimated Potentially Preventable Complications Cost Based on Hospital Charge Data States of California andMaryland

California Utiliza tion Maryland Utiliza tion

Number of Discharges Incremental PPCCost ($) Number of Discharges Incremental PPCCost ($)

Acute Pulmonary Edema and Respiratory Failure withoutVentilation

5,712 7,109 4,863 5,983

Pneumonia & Other Lung Infections 10,781 16,901 4,615 13,176Congestive Heart Failure 5,922 5,801 2,296 3,910Clostridium Difficile Colitis 2,478 25,401 1,282 16,709Urinary Tract Infection 12,677 9,637 6,904 6,345Cellulitis 2,907 4,950 1,435 2,346Post-Op Hemorrhage & Hematoma w/o Hemorrhage ControlProcedure or I&D Procedure

6,925 6,758 3,391 6,190

Source: Fuller, R.L., McCullough, E.C., Bao. M.Z., and Averill, R.F., 3M Health Information Systems, calculations using FY2008 Inpatient Acute Hospital Data, MarylandHealth Services and Cost Review Commission.


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based on actual hospital costs, stratified to includepatients with and without the PPC that were assigned tothe same All Patients Refined Diagnosis Related Groupsand severity of illness

A review of drivers of these costs at St. Joseph s Hos-pital Health Center and Crouse Hospital suggested thatincreased expenses for nursing, pharmaceuticals, anddiagnostic testing were most responsible. Theseexpenses were based on the cost of these resourcesrelated to lengths of stay at the hospital. Substantially longer stays for patients with the PPCs accounted forhigher use of resources by this group. The analysis didnot include separate analysis of the drugs consumed orthe procedures associated with the adverse events.

Evaluation of the impact of Potentially PreventableComplications involved the use of severity adjustedbenchmark data. Initial use of this information wasbased on California inpatient data for 2005 and 2006.Severity adjusted benchmarks from this source for medi-cal and surgical inpatients at Crouse Hospital and St.Joseph s Hospital Health Center in Syracuse during 2008are summarized in Table 5.

In addition to containing hospital benchmark data,this information comprised a summary of the incidenceof major Potentially Preventable Complications in Cali-fornia, the largest inpatient state database in the UnitedStates. The data indicate that the highest complicationrates per 1,000 hospital discharges were 7.04 - 10.20 forUrinary Tract Infections, 7.71 - 7.72 for AccidentalPunctures, and 5.22 - 8.73 for Pneumonia and OtherLung Infections.

Data related to Potentially Preventable Complications inthe Syracuse hospitals also involved early evaluation of programs for managing these outcomes that were imple-mented between October 2008 and March 2009. Thesecomparisons involved data for January-June 2008, the per-iod immediately prior to implementation of the projects,and January-March and April-June 2009, the most recentperiod for which coded inpatient data were available forthe hospitals. This information is summarized in Table 6.

This information demonstrated that, within these timeframes, complication rates had declined slightly for threeof the initiatives. These included decubitus ulcer, and posthemorrhage/acute anemia at St. Joseph s Hospital HealthCenter and pulmonary embolism at Crouse Hospital. Forthese projects, differences between hospital and severity adjusted benchmark rates fell from significant to nonsigni-ficant levels. The rate for urinary tract infection at Com-munity-General Hospital declined from nonsignificantly higher to nonsignificantly lower than the benchmark.These declines resulted from before and after compari-sons, rather than the use of control groups. In the partici-pating hospitals, it was not possible to develop controlgroups within the scope of the study.

These comparisons also demonstrated that differencesbetween hospital and severity adjusted PPC ratesincreased for urinary tract infection and decubitus ulcerat Crouse Hospital and for clostridium difficile colitis atCommunity-General Hospital. Only the increase forurinary tract infection reached a significant level. Thesedeclines resulted from before and after comparisons,rather than the use of control groups.

Table 4 Hospital Inpatient Cost Comparisons Patients With and Without Selected Complications Syracuse Hospitals January - June 2008

Patients with PPC Patients at Risk for PPC SignificanceLevel

Number of

Discharges

Total

Cost

Mean Cost Per

Discharge

Number of

Discharges

Total

Cost

Mean Cost Per

DischargeCommunity General Hospital

Urinary Tract Infection 40 829,599 20,740 842 9,806,054 11,646 p < 0.05Clostridium Difficile Colitis 10 267,747 26,775 253 2,716,270 10,736 p < 0.05Decubitus Ulcer 9 198,671 22,075 413 4,829,114 11,693Post Hemorrhage & Other AcuteAnemia w Transfusion

13 201,658 15,512 373 5,723,682 15,345 p < 0.05

Crouse HospitalUrinary Tract Infection 35 844,579 24,131 3,601 14,906,383 4,140 p < 0.05Decubitus Ulcer 5 165,222 33,044 421 2,250,905 5,347Pulmonary Embolism 9 164,630 18,292 266 2,148,818 8,078

St. Joseph s Hospital Health CenterPneumonia 84 5,425,856 64,594 3,152 41,081,238 13,033 p < 0.05Decubitus Ulcer 26 2,398,773 92,261 8,564 22,658,533 2,646 p < 0.05



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These data suggested that, based on the average cost dif-ferences identified in Table 4, the financial impact of managing complications could be considerable. This point

was based on simple calculations of the impact of changesin complications at the Syracuse hospitals during the per-iod of the study, rather than a specific analysis. For exam-ple, declines in PPC rates at St. Joseph s Hospital HealthCenter between January-June 2008 and January-March2009 reduced the first quarter costs for patients at risk of pneumonia by $386,707.50 and for those at risk of decubi-tus ulcer by $134,422.5. These expenses would translateinto annualized savings of $1,546,830 for pneumonia and$537,690 for decubitus ulcer. For Crouse Hospital, thedecline in complication rates produced a first quarter sav-ings of $20,218. For Community-General Hospital, the

decline in complications for urinary tract infections pro-duced a savings $90,940.

The demonstration project in Syracuse will generate

additional information concerning the impact of clinicalinterventions on a range of inpatient complicationswithin urban, general hospitals. It is projected to con-clude at the end of 2010.

DiscussionThis study described, in a preliminary manner, the useof the Potentially Preventable Complications system toevaluate hospital complications, related costs, and interventions to address these outcomes. It approached thesubject in a preliminary manner because this relation-ship is only beginning to be explored. The study

Table 5 Benchmark Rates of Major Potentially Preventable Complications Medical/Surgical PPCs January - September2008 Annualized

Range of Major PPC Rates/1,000 DischargesBased on Syracuse Hospitals Experience

01 Stroke & Intracranial Hemorrhage 1.18 - 2.56

02 Extreme CNS Complications 0.44 - 0.85

03 Acute Pulmonary Edema and Respiratory Failure with Mechanical Ventilation 2.80 - 5.83

04 Pneumonia & Other Lung Infections 5.22 - 8.73

05 Aspiration Pneumonia 2.25 - 3.02

06 Pulmonary Embolism 0.65 - 0.88

07 Shock 1.74 - 3.26

08 Congestive Heart Failure 3.85 - 6.56

09 Acute Myocardial Infarct 2.28 - 3.73

10 Ventricular Fibrillation/Cardiac Arrest 2.89 - 5.27

11 Peripheral Vascular Complications Except Venous Thrombosis 0.37 - 0.94

12 Venous Thrombosis 1.62 - 2.77

13 Major Gastrointestinal Complications with Transfusion or Significant Bleeding 0.36 - 0.5314 Major Liver Complications 0.43 - 0.73

15 Clostridium Difficile Colitis 1.13 - 1.66

16 Urinary Tract Infection 7.04 - 10.20

17 Renal Failure with Dialysis 0.40 - 1.11

18 Post-Hemorrhage & Other Acute Anemia with Transfusion 1.53 - 2.09

19 Decubitus Ulcer 0.84 - 1.34

20 Septicemia & Severe Infections 4.09 - 6.46

21 Post-Op Wound Infection & Deep Wound Disruption with Procedure 0.36 - 0.34

22 Reopening Surgical Site 0.97 - 1.71

23 Post-Op Hemorrhage & Hematoma with Hem Cntrl Proc or I&D Proc 0.78 - 2.32

24 Accidental Puncture/Laceration during Invasive Procedure 7.72 - 7.7125 Post-Procedure Foreign Bodies 0.13 - 0.17

26 Encephalopathy 1.03 - 1.84

27 Iatrogenic Pneumothrax 0.47 - 0.70

28 Mechanical Complication of Device, Implant & Graft 0.62 - 1.11

29 Inflammation & Other Complications of Devices, Implants o r Graft s Except Vascu lar Infect ion 1.74 - 3.12

30 Infections Due to Central Venous Catheters 0.00 - 0.00

Syracuse hospitals experience based on Crouse Hospital and St. Joseph s Hospital Health Center data applied to California statewide data, 2005 - 2006.


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included simple cost estimates of the impact of compli-cations on hospital resource use based on administrativedata. These estimates were based on statewide chargedata and hospital actual costs concerning directexpenses for specific hospitals. The study also described

use of the system to plan and implement interventionsto reduce complications.

The early Dutch research on this subject has beeninteresting. It suggests that there are important costimplications of a wide range of adverse health care

Table 6 Potentially Preventable Complications Programs Implemented Between October - December 2008 SyracuseHospitals January - June 2008, January - June 2009

Dates Discharges withMajor PPC Total

Cases

Major PPC Rate/ 1,000 Discharges

% Difference Significance Level

Actual Expected Actual ExpectedUrinary Tract Infection

Crouse Hospital Jan - Jun 08 43 55.9 5.43 7.05 -23.03

Jan - Mar 09 39 27.9 10.44 7.46 39.92 p < 0.05

Apr - Jun 09 27 20.4 9.96 7.52 32.43

Community General Jan - Jun 08 46 41.3 12.65 11.34 11.49

Hospital Jan - Mar 09 13 18.7 7.56 10.91 -30.67

Apr - Jun 09 17 20.0 10.02 11.79 -15.06

Pneumonia

St. Joseph

s Hospital Jan - Jun 08 145 112.0 10.09 7.79 29.46 p < 0.05Health Center Jan - Mar 09 42 31.0 12.34 9.11 35.48

Apr - Jun 09 34 27.0 11.69 9.28 25.93

Clostridium Difficile Colitis

Community General Jan - Jun 08 12 4.9 2.99 1.22 144.20

Hospital Jan - Mar 09 7 2.3 3.73 1.21 209.10

Apr - Jun 09 4 2.5 2.13 1.32 60.99

Decubitus Ulcer

Crouse Hospital Jan - Jun 08 6 7.1 0.71 0.85 -15.69

Jan - Mar 09 5 3.1 1.28 0.79 62.57

Apr - Jun 09 3 2.3 1.06 0.83 28.58

St. Joseph s Hospital Jan - Jun 08 31 13.0 3.41 1.43 138.47 p < 0.05

Health Center Jan - Mar 09 9 6.0 2.12 1.41 50.00

Apr - Jun 09 7 5.0 1.95 1.39 39.99

Pulmonary Embolism

Crouse Hospital Jan - Jun 08 12 5.1 1.53 0.65 133.80 p < 0.05

Jan - Mar 09 5 2.5 1.32 0.65 101.44

Apr - Jun 09 2 1.8 0.73 0.67 9.24

Post-Hemorrhage & Other Acute Anemia w Transfusion

St. Joseph s Hospital Jan - Jun 08 55 16.0 7.36 2.14 243.75 p < 0.05

Health Center Jan - Mar 09 11 8.0 3.04 2.21 37.50

Apr - Jun 09 5 7.0 1.67 2.34 -28.57



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outcomes. This type of wide view of the subject is extre-mely necessary given current limitations on health careresources. More studies of this nature will be of greatbenefit to health care policy makers and providers.

The research from the United States presented in thearticle was of a more focused nature. It involved a singlecategory of adverse outcomes, complications that developwithin hospitals after inpatient admission. As an example,the complications data suggested what will be necessary if the management of health care outcomes is to move fromthe shadows where it has resided to become a major focusfor cost containment, as well as the improvement of care.

In the United States, hospital reimbursement is based onprospective payments per discharge for public and privatepayors. Under this system, hospitals are paid a relatively fixed rate per patient. This encourages efficiency throughreduction of complications, extended stays, and other

developments which consume hospital resources. The cur-rent system includes a small penalty for the presence of inpatient complications. The amount of this penalty ismuch lower than the potential excess costs related tocomplications that were identified in this study.

In this context, the developing experience with inpati-ent hospital complications in the United States demon-strates the resources that are needed for this to occur.At the technical level, these include categories withinadministrative data, such as the Present on Admissionindicator, that make it possible to collect and analyzeoutcomes data at the provider and regional levels.These resources also include software that focuses onthe indicator through a sophisticated system of logic. Itseems clear that the Potentially Preventable Complica-tions algorithm, although still under development, con-tains the exclusions and criteria necessary to convertadministrative data, including the Present on Admissionindicator, to usable information. The linkage betweenthe PPC software and the All Patients Refined Severity of Illness System produces the ability to analyze andcompare outcomes data by level of illness within hospi-tals and large populations. The availability of thisresource is helping to move quality assurance staff inhospitals like those in Syracuse from record keepers to

clinical managers.Current information also suggests that efforts to

improve health care outcomes such as complications inthe United States will benefit from the historical pressureto reduce health care costs which have been compoundedby the impact of the recent economic recession. It seemsclear from recent pronouncements from Washington thatthe Obama Administration believes strongly that there is aconnection between health care outcomes and costs.Complications are not the only indicator that is benefitingfrom the attention. Reduction of hospital readmissions hasalso become a focus of attention. The federal Medicare

program is interested in redesigning hospital reimburse-ment to address this objective [ 30].

ConclusionsAll of this suggests that, after years of struggling forgreater attention within the provision of health care andthe policy making that surrounds it, the monitoring andmanagement of quality and outcomes may be about tomove to the forefront. The development of the Poten-tially Preventable Complications algorithm is an exampleof this process. Historically, Europe and the UnitedStates have been the major sources of research andinnovation concerning health care utilization and out-comes. The new opportunities can benefit both sides of the Atlantic if commitments are made to ensure thatthe necessary data and analytic tools are available. Now is the time to ensure that preliminary efforts, such as

those described in this article, receive adequate support.

Author details1 Hospital Executive Council Syracuse, New York, USA. 2National Institute forPublic Health and the Environment Bilthoven, Netherlands.

Authors contributionsRJL participated in planning the analysis, developed the data concerning thecosts of complications, and coordinated the implementation of interventionsin the hospitals of Syracuse, New York. GPW developed the structure of thestudy, contributed to the collection of the literature, and participated inplanning the analysis. Both RJL and GPW developed the revisions to themanuscript which resulted in the final version. Each of the authors read andapproved the final manuscript.

Authors

informationDr. Ronald J. Lagoe (1)Prof. dr. Gert P. Westert (2,3)1 Hospital Executive Council, PO Box 35089, University Station, Syracuse,New York, 13235, USA2 Tilburg University, TRANZO, PO Box 90153, 5000 LE Tilburg, TheNetherlands3 RIVM National Institute for Public Health and the Environment, PO Box 1,3720 BA Bilthoven, The Netherlands

Competing interests The authors declare that they have no competing interests.

Received: 23 December 2009 Accepted: 9 July 2010Published: 9 July 2010

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doi:10.1186/1472-6963-10-200Cite this article as: Lagoe and Westert: Evaluation of hospital inpatientcomplications: a planning approach. BMC Health Services Research 201010:200.

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